Media producers, media providers, advertisers, product manufactures represented in advertisements, and many other entities utilize information about the presentation of media. Such information is often collected through the use of panels comprised of persons (e.g., panelists) who have agreed to have their exposure to media monitored. For example, audio of media may be transmitted with identifying information (e.g., embedded watermarks or codes) that identifies the media. Panelists may be supplied with meters (e.g., portable meters carried and/or worn by the panelists) that collect the audio and extract the identifying information. The information may be transmitted to a collection facility where the results from multiple panelists are combined to generate reports comprising information about media presentation.